25nm pitch master and replica mold fabrication for nanoimprinting lithography for 1Tbit/inch2 bit patterned media

Nanoimprint Lithography and a mold, mold replication from an EB master mold as well, those are essential for a large-scale production of bit patterned media. 1Tbit/inch2 (bit pitch 25nm) areal density on a 2.5inch HDD media, it is feasibility demonstration target all the media makers and the HDD makers are aiming at. This paper describes difficulties we faced, and solutions we established by designing and optimizing materials and process, to fabricate 25nm pitch master mold by EBL as well as working replica mold by NIL.